Nowadays, most electronic devices such as cell phones, portable media players, and notebooks including netbooks and tablet computers, usually are equipped with touch panels serving as input interfaces of the new generation to replace the conventional mousse and keyboards.
The touch panel has a plurality of sensors for detecting a touch or touches. The touch panel has a matrix of points. One or more points of the touch panel are touched when an object touches the touch panel. The point that is touched is referred to as a “touch point” herein. The sensors are used to sense the sensing value or values (e.g., capacitance(s)) of the touch point or points when a touch occurs on the touch panel. The sensing values and corresponding positional information of the touch points are transmitted to a rear end circuit. Conventionally, the rear end circuit will determine a touch coordinate for the touch by calculating a centroid coordinate based on the sensing values and the positions of the touch points.
A conventional touch position detecting method in US Publication No. 2011/0087455 discloses a centroid calculation based on the differences between two neighboring signal values for determining the touch coordinate. Additionally, in US Publication No. 2010/0252336, a position method for a touch device is disclosed and said method utilizes another centroid calculation to determine the touch coordinate, wherein said centroid calculation is based on the square root of the sensing value.
The present invention provides a novel and inventive method for making the calculation result of the touch coordinate more stable.